The objective of this program is the continued development and testing of the extracorporeal pulsatile assist device (EPAD), a valve-less, single usage, disposable blood pump designed for short- term circulatory support. Using simple molded components and fabrication methods appropriate for a temporary device, the EPAD can be made available at a cost comparable to the intraaortic balloon pump (IABP), while providing significantly better performance. The EPAD is also comparatively easy to implant and operate, and it may be driven with existing IABP drive consoles, making it usable at virtually any center currently performing cardiac surgery. The EPAD has been shown to be an effective right ventricular assist device. It is similarly useful as a left ventricular assist device providing diastolic augmentation, and when used to provide transapical systolic augmentation, it may be of value as a bridge to transplantation in patients awaiting a cardiac allograft. Because the EPAD offers superior performance relative to the IAPB, and also because it is useable in surgical patients in whom an IABP cannot be employed because of arterial disease, the EPAD has the potential to capture a share of the IABP market as well as being usable in the comparatively small number of postcardiotomy and pretransplant patients who require circulatory support.